RFID systems are well known in the art. Such systems include relatively large packages containing battery powered transmission/receiving circuitry, such as the identification system disclosed in U.S. Pat. No. 4,274,083, to passive systems in which the transceiver receives its power from the base station or interrogator, such as the identification system disclosed in U.S. Pat. No. 4,654,658.
A typical RFID system is made up of reusable tags fixed to or embedded in product carriers, antennas that interrogate the tags via a RF link and a controller. The host (or computer) system interfaces with the controller and directs the interrogation of the tags.
RFID tags provide effective means of identifying, monitoring and controlling materials in a closed loop process. In the factory, tags are employed as the transport mechanism between “islands of automation,” providing a record of each process which can be acted upon immediately or downloaded later for analysis.
The tags can be powered by an internal battery (i.e., an “active” tag) or by inductive coupling (i.e., a “passive” tag). Passive tags have zero maintenance and virtually unlimited life. The life span of an active tag is, however, limited by the lifetime of the battery, although some tags offer replaceable batteries.
RFID tags are packaged in a variety of forms and are fastened by a multitude of means. The tags are typically encapsulated for durability against shock, fluids, dust or dirt.
There are, however, several drawbacks associated with conventional RFID tags. First, the tags have limited applicability due to range limitations. Second, as indicated above, the tags are typically permanently fixed to or embedded in the product carriers (e.g., shipping containers). Thus, any data acquired during packaging and/or shipping does not accompany the product upon removal from the shipping container.
It is therefore an object of the present invention to provide a RFID tag assembly and system that provides means for tracking a product or other article after removal from a transport medium.
It is another object of the invention to provide a RFID tag assembly and system that extends the operating range of a conventional RFID tag.
It is yet another object of the invention to provide a RFID tag assembly and system that reduces orientation sensitivity of a conventional RFID tag.